Pontiac , Michigan -LRB- CNN -RRB- -- Lamont Butler is a single father , unemployed for more than a year and trying to do the best for his daughter , 3-year-old Samaya . The family qualifies for the federal government 's free pre-kindergarten program , Head Start , but has been on a waiting list for more than a year .

It 's tough on both of them ; Butler has trouble finding work because he 's caring for his daughter , and he worries Samaya is missing out on valuable early education .

`` My friend 's son got in , and at 4 , he can already spell his name , do simple math , and he is n't so shy any more , '' Butler said .

But Butler 's daughter is one of thousands on waiting lists for the 49,000 Head Start classrooms around the country - a list that might get shorter after an investigation into allegations of fraud by some applicants and Head Start workers .

A U.S. Government Accountability Office investigation that concluded in May showed that several Head Start workers committed fraud to enroll families whose incomes were above the federally mandated limit .

Head Start is open to foster and homeless children , kids with some disabilities , families eligible for government assistance and families with incomes below the federal poverty guideline , about $ 22,000 for a family of four . Programs may enroll limited numbers of kids whose parents make more money .

$ 9 billion went to support Head Start in 2010 , and more than 900,000 children are enrolled in programs around the United States .

The investigation began two years ago , after whistleblowers called the GAO 's tip line and alleged that Head Start workers in the Midwest and Texas admitted families that made too much money to qualify . Documents that whistleblowers leaked to the GAO showed that some workers admitted children whose parents made more than $ 110,000 . In some cases , according to the GAO , workers may have lied or manipulated documents so their programs appeared to be within mandated enrollment targets .

`` Taxpayers are being ripped off , '' said Greg Kutz , the managing director of forensic audits and special investigations for the Accountability Office . `` The real risk here is that the over-income children were being served , and the poorest children in our country are losing the benefit of Head Start . ''

A 10-year study released in 2010 by the U.S. Department of Health and Human Services showed that Head Start kids are better prepared academically and socially to enter kindergarten . They have better language skills and are better at making friends and handling classroom settings . Parenting skills improved , too , among those whose kids were in Head Start , according to the HHS study .

Head Start is popular , too , because it 's free , while private preschools and day care can cost more than $ 10,000 per year .

To investigate the complaints , Kutz sent staff members armed with hidden cameras to pose as parents interested in Head Start enrollment . When parents apply , they must present tax records , pay stubs or public assistance documents that prove they meet the federally mandated income standards . The investigators ' documents showed they made too much money to enroll , but at eight of the 15 Head Start centers they approached , staff members pretended they had n't seen the income levels , or they urged parents to lie .

In a tape Kutz showed to Congress in May , one Head Start worker examined the investigators ' documents and said , `` This is over income . ''

When the undercover investigators asked what to do , the Head Start worker suggested they did n't have to put both parents ' incomes on the form .

With a laugh , she added , `` I 'm not supposed to say that . '' Another staffer joked , `` Now you see it , now you do n't . ''

Kutz said he does n't believe these are isolated cases .

`` It 's pretty disturbing , '' Kutz said . `` I believe the system is very open to fraud . ''

The problem , Kutz said , is that Head Start workers only have to sign a statement that they 've seen proof of parents ' incomes . Federal rules do n't require Head Start offices to keep income documents on file .

`` If you want to go in and say you are unemployed , you could get benefits even if you were making $ 100,000 because -LSB- Head Start was n't -RSB- validating anything , '' Kutz said .

Not all Head Start programs have been letting the income rules slide . Michigan 's Oakland Livingston Human Service Agency , where Lamont Butler hopes to enroll his daughter , has long kept copies of parents ' income documents .

`` Our goal is to exceed those standards '' for documents , said Lynn Crotty , the program 's director . `` In always maintaining copies of proof of income in our files , that 's enabled us to ensure that the families that deserve to be in the program are the ones who are getting into the program . ''

Yvette Sanchez Fuentes , Head Start 's national director , said she took action immediately after learning about the federal investigation last spring .

`` We know that what went on the tape , -LSB- that the worker -RSB- engaged in some fraudulent behavior , '' she said .

Sanchez Fuentes said the system is n't broken .

`` I think it 's important to note those are individuals within those programs , '' she said . `` We know the majority of Head Start programs across the country are doing the right thing . ''

According to Sanchez Fuentes , Head Start officials advised local directors about enrollment procedures , bulked up on admissions training and now make unannounced visits to local programs . A new Health and Human Services tip line lets workers report fraud to the department , which oversees Head Start , instead of going straight to the GAO .

'' -LSB- President Obama 's -RSB- administration will not tolerate any type of fraud , waste or abuse , '' Sanchez Fuentes said . `` We will make sure that when we go out to see these local programs , that they are indeed doing the right things and that every federal dollar that goes to Head Start is not being misused . ''

Still , they have not yet taken Kutz 's suggestion to change the policies about keeping income eligibility documents . The issue is up for a 90-day comment period , but the rule wo n't change unless Head Start leaders decide it 's the best course of action .

Demand for Head Start remains strong , even in programs where there 's no suspicion of fraud . For parents like Butler and kids like Samaya , that means the wait continues .

`` The time we spend together has meant the world to me , but the things I 've taught her are only things I know , '' Butler said . `` I know they could do a much better job . ''

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An investigation into Head Start enrollment practices shows some centers enroll families who make too much money

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Thousands are on waiting lists for the free pre-kindergarten classes

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Head Start leaders are adding more training , checks to enrollment to prevent fraud